lyo LIFE AND HABIT. 



II. We should expect to find that the offspring, 

 whether in its embryonic condition, or in any stage of 

 development till it has reached maturity, should adopt 

 nearly the same order in going through all its various 

 stages. There should be such slight variations as are 

 inseparable from the repetition of any performance by 

 a living being (as contrasted with a machine), but no 

 more. And this is what actually happens. A man may 

 cut his wisdom-teeth a little later than he gets his 

 beard and whiskers, or a little earlier ; but on the whole, 

 he adheres to his usual order, and is completely set off 

 his balance, and upset in his performance, if that order 

 be interfered with suddenly. It is, however, likely that 

 gradual modifications of order have been made and then 

 adhered to. 



After any animal has reached the period at which it 

 ordinarily begins to continue its race, we should expect 

 that it should show little further power of development, 

 or, at any rate, that few great changes of structure or 

 fresh features should appear; for we cannot suppose 

 offspring to remember anything that happens to the 

 parent subsequently to the parent's ceasing to contain 

 the offspring within itself ; from the average age, there- 

 fore, of reproduction, offspring would cease to have any 

 further experience on which to fall back, and would 

 thus continue to make the best use of what it already 

 knew, till memory failing either in one part or another, 

 the organism would begin to decay. 



To this cause must be referred the phenomena of old 

 age, which interesting subject I am unable to pursue 

 within the limits of this volume. 



